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Which water pump should I run for an LS swap: truck pump or Camaro pump?

It depends on your accessory drive spacing and whether your engine has VVT — the pump has to match the balancer and brackets you're running.

Last updated

Pump Spacing Gen Outlet Clears a VVT timing cover Example part
LS1 water pump -1 Gen III car style No ICT WAT200
LS3/LSA/LS7 Corvette pump -1 Gen IV car style No ICT WAT101
Gen III truck pump -3 Gen III vertical outlet on top No ICT WAT300
Gen IV truck pump -3 Gen IV vertical outlet on top Yes ICT WAT301
LS3/L99 Camaro pump -3 Gen IV outlet upper driver side Yes ICT WAT302

How to choose:

  • Match the spacing of your balancer and accessory brackets: -1 (Corvette/car), -2 (F-body Camaro/Firebird), -3 (truck). Mixing spacings misaligns the belt — see the accessory spacing picker.
  • VVT engines (many Gen IV trucks): only the Gen IV truck pump and the LS3/L99 Camaro pump clear the VVT timing cover.
  • The LS1 pump is the most flexible: direct fit on -1 and -2 drives and usable on -3 with ICT's spacers, but it doesn't clear a VVT cover.
  • Outlet position matters for hood and radiator hose routing: truck pumps have a vertical outlet on top; car pumps route differently. Most LS water pumps have both inlet and outlet on the passenger side; LS swap radiators put both ports on the passenger-side tank.

See the accessory drive guide.

What we recommend

The simplest path is to keep the stock truck pump and accessories: run the heater lines to the truck pump ports, route the steam vent line to the old heater-return nipple on the stock radiator, and use stock LS truck upper and lower hoses. If you want the Camaro-style pump so you can use stock squarebody hoses, use the L99 Camaro pump, not the LS3 pump, because it matches truck/SUV belt spacing. That route also needs the ICT Billet idler relocation kit, trimming an ear off the alternator/PS bracket, a '99-07 NBS truck lower hose and an '06 Corvette upper hose.

Check this first:

  • These clearance notes assume Tejas Steelworks mounts, which put the engine 1 in up and 1 in forward
  • Don't mix Envoy/Trailblazer pumps and brackets with truck parts, since the bolt patterns differ

Based on what we've seen work across our own builds, our friends' builds and the wider LS community, reviewed by our lead shop tuner (over 20 years of LS and LT tuning experience). Every combination is different, so use at your own risk and check our safe tuning limits before any wide-open pass.

Go deeper

Check this first

  1. Identify which accessory drive spacing the swap uses before buying a pump

Try this, then this

  1. Match pump to existing accessory spacing, or spacer to adapt — pulley alignment. Worked if: belt runs true

How you know it's fixed

  • Pulley planes align; belt tracks straight

Still not fixed?

  • Re-measure crank pulley to water pump pulley offset

Key numbers

WhatValue
Belt spacing ladderCorvette/G8/CTS-V tightest; LS1 Camaro 3/4 in outboard; truck & 2010+ Camaro another 3/4 in
ICT spacer for Camaro pump on truck spacing551690-71, 0.71 in, ~$58.99

Every option we know of

We may earn a commission when you buy through links on this page.

Maker / productPart #FitsPriceWhereStatus / notes
GM
L99/LS3 Camaro water pump		19257334truck-spacing accessory drivesabout $150GM dealerIn production
ICT Billet
water pump spacer 0.71 in		551690-71Camaro pump to truck spacing$58.99Buy
ICT dealers		In production
GM
truck water pump		n/atruck spacingabout $120GM dealerIn production
taller, may hit hood

Prices are approximate as of September 2026. We list every option we know of, including small shops and used parts we can't link to. Confirm fitment with the seller.

Time and cost: Pump swap: 2-3 hours

Why do I smell coolant but can't find a leak?
What we recommend

The water pump weep hole, hidden behind the pulley, is our top suspect when you can smell coolant but can't see a leak, and a failing seal there can go months before it shows itself. The water-pump-to-block gaskets are another common drip point; the thin stamped-metal OEM gasket with its orange O-ring can weep, and we recommend thicker fiber replacement gaskets (about $10 in 2014). Also check the overflow tank seams, radiator hoses and heater core lines, and look for wetness on the front of the K-member. A radiator pressure test is the quickest way to pinpoint an elusive leak, and a UV dye kit (under $20) will reveal leaks you can't otherwise see.

Check this first:

  • Water pump weep hole behind the pulley
  • Water-pump-to-block gaskets
  • Overflow tank seams and heater core lines

Careful: Only open or pressure-test the cooling system with the engine cool, since hot coolant under pressure can cause burns.

Check this first

  1. Check for drip immediately after a drive, while hot

Try this, then this

  1. Pressure test, then replace pump if weep hole leaks — seal is done. Worked if: smell gone

How you know it's fixed

  • No coolant smell; level holds for a month

Still not fixed?

  • Check heater hoses, radiator seams, and intake steam vents

Key numbers

WhatValue
Weep hole drip diagnosisseal failure; replace the water pump
Pressure test15-20 psi

Every option we know of

Maker / productPart #FitsPriceWhereStatus / notes
ACDelco
water pump		252-846truck LSabout $120Buy
parts store		In production
GM
water pump		19257334Camaro LS3/L99about $150GM dealerIn production

Prices are approximate as of September 2026. We list every option we know of, including small shops and used parts we can't link to. Confirm fitment with the seller.

Time and cost: 2-3 hours

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